The present invention relates to an electro-hydraulic control apparatus for a motor-vehicle transmission, in particular for a transmission with six or seven forward gears and one reverse gear, either of the double-clutch type or of the single-clutch type derived therefrom.
European Patent Application EP 1965101 in the name of the Applicant discloses an electro-hydraulic control apparatus for a motor-vehicle double-clutch transmission with six or seven forward gears and one reverse gear, which control apparatus comprises a gear shift control device and a hydraulic control circuit. The gear shift control device includes four shift forks operatively associated each to a respective engagement sleeve of the transmission to cause this latter to move between first and second engagement positions, and an actuating unit comprising four double-acting hydraulic actuators arranged to control each the displacement of a respective shift fork. The hydraulic control circuit comprises a supply unit, a slide valve for selecting each time one of the four hydraulic actuators and two gear shift solenoid valves for controlling the hydraulic actuator selected each time by the slide valve to carry out the engagement of either one of the gears associated to this actuator. The slide valve has four operating positions, each of which corresponds to the selection of a respective hydraulic actuator, and is displaceable between these four operating positions by means of a special pilot solenoid valve. A position sensor is advantageously integrated into the slide valve to allow it to be position controlled.
German Patent Application DE10125172 discloses an electro-hydraulic control apparatus for a motor-vehicle transmission having plurality of gears. This known control apparatus comprises four shift forks each movable in at least one engagement position to engage a respective gear, four hydraulic actuators each arranged to control the movement of a respective shift fork in the respective at least one engagement position, and a slide valve selectively movable into one of four operating positions in each of which the slide valve selects a respective hydraulic actuator.